{"cve":"CVE-2021-47475","nvd":{"published":"2024-05-22T09:15:09.370","modified":"2026-06-17T04:17:33.480","status":"Analyzed","description":"In the Linux kernel, the following vulnerability has been resolved:\n\ncomedi: vmk80xx: fix transfer-buffer overflows\n\nThe driver uses endpoint-sized USB transfer buffers but up until\nrecently had no sanity checks on the sizes.\n\nCommit e1f13c879a7c (\"staging: comedi: check validity of wMaxPacketSize\nof usb endpoints found\") inadvertently fixed NULL-pointer dereferences\nwhen accessing the transfer buffers in case a malicious device has a\nzero wMaxPacketSize.\n\nMake sure to allocate buffers large enough to handle also the other\naccesses that are done without a size check (e.g. byte 18 in\nvmk80xx_cnt_insn_read() for the VMK8061_MODEL) to avoid writing beyond\nthe buffers, for example, when doing descriptor fuzzing.\n\nThe original driver was for a low-speed device with 8-byte buffers.\nSupport was later added for a device that uses bulk transfers and is\npresumably a full-speed device with a maximum 64-byte wMaxPacketSize.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","score":7.8},"cwes":["CWE-787"],"references":["https://git.kernel.org/stable/c/06ac746d57e6d32b062e220415c607b7e2e0fa50","https://git.kernel.org/stable/c/199acd8c110e3ae62833c24f632b0bb1c9f012a9","https://git.kernel.org/stable/c/278484ae93297b1bb1ce755f9d3b6d95a48c7d47","https://git.kernel.org/stable/c/33d7a470730dfe7c9bfc8da84575cf2cedd60d00","https://git.kernel.org/stable/c/40d2a7e278e2e7c0a5fd7e997e7eb63945bf93f7"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T21:50:30.954589733+00:00"},"epss":{"cve":"CVE-2021-47475","score":0.00259,"percentile":0.17596,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}